The present invention relates in general to scraper-chain assemblies for use in scraper-chain conveyors and more particularly to scrapers and scraper units therefor.
Scraper-chain assemblies of various designs are well known in the art. The present invention is particularly but not solely concerned with the so-called double-chain assembly where scrapers are mounted between a pair of widely spaced oval-link chains. In order to connect the scrapers to the chains various forms of connectors can be utilized. In one early simple design open shackles are inserted into the chains at intervals and are secured to the scraper. A more recent design has welded-on extensions to the scraper body which engage over horizontal links of the chains. Additional plates are clamped to these extensions with vertical screws and engage beneath the links. The extensions and the complementary plates can be shaped to co-operate and locate the chain links in grooves or recesses. One example of a scraper assembly of this type is described in German Patent Specification No. 1921747. In another known construction described in German patent specification No. 2105960 welded-on extensions to the scraper body engage beneath the horizontal chain links and open hook-like rings engage over the inner shanks of these links. Connectors then extend across the links from above to engage over the outer shanks and these connectors are secured to the scraper with horizontal screws extending parallel to the scraper. This construction necessitates tilting and other manoeuvring of the components when assembly or disassembly is taking place and it is preferable to employ a more simple vertical connection.
A general object of the present invention is to provide an improved scraper unit design.